1. Field of the Invention
This invention relates to conveyors.
2. Summary of the Invention
An object of the invention is to provide a new and improved conveyor.
According to one aspect of the present invention we provide a conveyor including at least two endless chains each comprising a plurality of pivotally interconnected links, each link comprising a synthetic plastics material, having a conveying surface, and having attachment means whereby additional elements may be mounted thereon and at least some of the links in each chain being engageable by a drive means.
The pivotally interconnected links transmit the whole of the driving, or tension, loading in the conveyor and the additional elements transmit no such load. Hence it is necessary for only the links to be made sufficiently strongly to accommodate such tension loading and the additional elements may be made of any suitable material. For example, the additional elements may be made of a material which, whilst it cannot accommdate the tension loading of the conveyor, it is more suitable for its intended purposes, for example the material may be a relative cheap material and hence leading to more economical production of the additional elements or, if relatively high frictional properties are required, the additional elements may be made of a rubber material which would provide the necessary frictional properties without having the strength which would be necessary to accommodate the tension loading of the conveyor.
Preferably, each link is of a one-piece construction, such as a moulding or an extrusion in synthetic plastics material.
The links may be pivotally interconnected by pivot pins which are received in passages formed in the links and the parts of the links in which pins are received may be engageable by the drive means. The drive means may comprise a suitably shaped sprocket.
At least some of the links may be provided with a plurality of apertures in which are received mounting means provided on the additional elements whereby the additional elements are mounted on the links.
The additional elements may be attachable and detachable by movement thereof only in a direction normal to the conveying surface and means for retaining the elements on the links may be provided said means being operable to secure and release the elements without disassembling the chain or gaining access to the under side thereof.
The additional elements may be provided with projections which snap inter-engage with the apertures in the links.